New stack questions

[maple flats]

I just received the new SS stack for my Grimm arch. I have a question. Having been in the wood furnace business before retiring, I had been taught (by a master tinsmith) to have the seams so the upper section always fit inside the lower stack. This kept any leakage (rain, creosote, etc.) from running down the outside and leaving streaks or worse. When I removed the old badly rusted stack that had come with the arch, pre-assembled, everything was put together with the upper going over the lower, the exact opposite of my training. When I took it apart, there was lots of ash/soot caught at the top of the base stack where it left a considerable ledge where the 1st section of stack just rested on top of the base leaving a place for such to be caught.
Do all stacks go like this, or have some of you been able to get the crimp end to slide inside the top of the base stack? On my Leader base and stack it doesn't look possible. My idea is to have my sheet metal shop adapt the base to make it right (the current owner's grandfather is the one who taught me the crimps should always face down on vertical runs).
Does everyone just do it the easy (but wrong) way?
I'm thinking I might have the base stack altered and weld an adapter to the top that will accept the crimp end.
Comments please.

[jmayerl]

I had mine custom made and I was done the "right way" that you were taught.

[SeanD]

So, I have mine "the wrong" way, but I have to do it that way b/c the top of the base stack is the crimped end. I had always thought of it from the smoke point of view - that the smoke and ash would travel up past the seam.

Sean

[sugarsand]

I did ours the same way that we have always done stovepipe, and that is to slide the bottom of the top piece over the top of the bottom piece. The theory was that this way you dont have a edge directly against the flow of exhaust gasses and soot, reducing build up in the pipe. I dont know if this is right or wrong but just the way I was taught to do it.

Sugarsand

[sugarsand]

Dave, do you leave your stack up year around? We used to take ours down after sugaring till we got the stainless, now its up permanant. One less job in the spring. The rain cap can be opened and closed from inside the boiling shed.

Sugarsand

[lew]

I think you are doing it the right way flats. Have the upper section go into the lower section. As you stated all of your rain water will stay inside the pipe and not make unsightly streaks on the outside of your pipe, and more importantly, you wont get a buildup in the joint between the pipe sections with it installed this way. I do think that you will loose a very small amount of draft due to increased drag. But most pipes are large enough to accommodate that. I had my base stacks custom built and had them made so the upper section went into the lower. Wouldn't have it any other way.

[lpakiz]

On our Intensofire clone, each section goes inside the one below, so as to channel water towards the inside. However, we get a quite a few sparks escaping inside the shack, because of the pressure. If I did it again, I would change it so the flow of gases was kept inside the pipe.
Actually, I contemplated using a double ended section, (crimped ends on both ends) which would be located where the stack exits the roof. This would channel sparks towards the inside until the stack exited the roof, where it would become a rain-shedding stack. I would not care if sparks escaped once the stack was above the roof. Comments??

[maple flats]

Yes, mine stays up all year and I have a cap that opens and closes. I have high pressure AOF and we never see any sparks, inside nor out. I'm going to have my tin shop convert it by welding an adapter to the top of the base stack. Even though the cap closes, at times in a hard rain moisture still escapes to streak down the outside in a hard downpour when boiling. The biggest issue to me however is the catch ledge where the base tapers in and the stack rests on the outside of the base stack. That leaves corrosive soot to attack the integrity of the base stack. When I pulled my old (yes it was galv, not SS) the top lip that caught the soot, was very weak and flimsy from being attacked by the soot it held. Even with a cover closed, humid air gives the soot the right conditions it needs to cause damage in time. At my age (I can see 68 coming in full at gallop), my hope is that this new stack will be my last one to buy, and as I pass the operation on to the next generation, it will still be good.

[maple flats]

By the way, my guess on why the base stacks are not made to fit the crimp end of the next section inside it is just because it is far easier for them, no precision needed, thus saving time for the manufacturer. It also creates a degree of job security, because stacks need replacing sooner and they will gladly build a new one at a high price for you.

[PerryW]

My original 15: galv. stack only lasted about 6 years. I replaced it with SS and it's still going strong 19 for 19 years. I believe the crimps are facing down so water running down the outside will not get inside the stack.

[maple flats]

I just picked up my redesigned stack today. The shop cut the top of the Leader SS stack so it is square and even, and sized slightly larger than the 12" top stack. Then he made an adapter to insert into the top of the base and then to accept the 12" top stack. It looks great. I furnished the 20 ga bright annealed to use, he made the adapter and re-cut the base to fit it squarely. He charged $60, money well spent. Now I've go to hook it up and get things ready. I also need to buy more jugs because I need to re-pack another 40 gal BBL of DA into retail. My light and medium are still good, but my dark sells way faster.

[Mark-NH]

Can't but wonder if you are over thinking it.

[maple flats]

Maybe, but I hate seeing stains streaking down the outside of a stack, SS or galv. It just looks bad!

[maple flats]

I put the new base stack and adapter up on the arch today. It looks nice. Now I need to decide what I'm going to do before I finish.
My last stack (galv.) had 2 extra layers, each spaced out 2" from the previous to protect the wood. This time I'm still trying to decide if I want to do it that way (in SS) or if I want to install the rest of the stack up thru the roof and protect the wood with either 2 layers of flat SS spaced out 1" on non combustible spacers, or use some ceramic insulation. The 2 SS options would likely look neater but all 3 methods will do the job.